Oxygen demand pressure breathing regulator



S p 1 0 H. P. ROTH 2,521,310

OXYGEN DEMAND PRESSURE BREATHING REGULATOR Filed June 19, 1945 2 Sheets-Sheet 1 INVENTOR.

HERMAN P. ROTH ATTORNEY Sept. 5, 1950 H. P. ROTH OXYGEN DEMAND PRESSURE BREATHING REGULATOR 2 Sheets-Sheet. 2

Filed June 19, 19 45 INVENTOR.

P. ROTH HERMAN ATTORNEY Patented Sept. 5, 1950 OXYGEN DEMAND PRESSURE BREATHING REGULATOR x Herman P. Roth, Rcdondo Beach, Calif., as-

signor to The Garrett Corporation, ,Airesearch Manufacturing Company division, Los Angeles;

'Calif., a corporation of California Application June 19, 1945, Serial No. 600,361

This invention relates to apparatus for controlling the supply of oxygen under pressure, through an oxygen mask or other breathing out let, to a human being for handling the requirements for adequate breathing at high altitudes.

' It is recognized that the human lungs at altitudes from 10,000 to 30,000 feet require for adequate breathing air which is progressively richer in oxygen at the higher altitudes, and that above 30,000 feet, even though pure oxygen is breathed, physiological impairment of the bodily functions will becomeincreasingly felt until at altitudes in the vicinity of 40,000 feet, it becomes necessary in order to avoid serious or disabling impairment of faculties, to supply oxygen to the lungs under pressure greater than atmospheric pressure. This may be accomplished by either placing the atmosphere within an aircraft cabin under pressure or by supplying oxygen or an oxygen mixture directly to the respirational organs of an individual. It is with the latter class of apparatus that the present invention deals, and general object of the invention is to provide an improved and simplified regulator for controlling the supply of oxygen or an oxygen mixture to the respirational organs in such a manner as to permit natural breathing under pressure without the need for expenditure of more than normal breathing efforts.

In general, the invention is embodied in a control device comprising a chamber having a connection to a suitable source of oxygen under pressure and another connection which leads to a mask worn by the user, the flow of oxygen through the chamber being controlled by a valve which, in turn, is controlled by a, diaphragm or other device sensitive to variations in pressure in the chamber produced by inhalation and exhalation of the user. When the user inhales, the pressure within the chamber is slightly reduced, the diaphragm causes the oxygen inlet to open, and oxygenflows through the chamber to the mask. When inhalation is terminated, thepressure within the chamber rises, the diaphragm causes the oxygen inlet to close, and a further rise in pressure caused by exhalation will effect the opening of an exhalation valve. In prior de vices it has been proposed to, embody such an exhalation valve in the chamber of the control device itself. The present invention contemplates the utilization of an oxygen mask having a'suitableexhalation valve and the provision of a regulator which simply permits a oneway flow therethroughin response to inhalation and upon exhalation builds up a back pressure in the mask 4 Claims. ('Cl. 128142) which causes the outlet valve to open. Such an arrangement has the very definite advantage of providing for the immediate discharge of foul air from the mask and the maintenance at all times of a column of pureQuncontaminated, oxygen within thetube connecting theregulator tothe mask pIus the added advantage of not causing condensation and freezing in the regulator 10 and connection 23 leading from the regulator l0 the mask 2'4, should the apparatus be used in low temperature surroundings.

One of the objects "of this invention isto provide a regulator capable of adjustment to vary the pressure at which the oxygen is supplied to the lungs.

. Another objectis to provide a regulator which will assure consistent ease of breathing and prop-. er balance between inhalational and exhalational.

pressure differentials throughout the range of pressures to which the regulator may be adjusted A further object is to provide a regulator which renders inhalational effort and the rate of oxygen inflow relatively independent of the oxygen sup-v ply pressure within -its usual limits of variation.

Another object is -to provide an oxygendemand;

regulator having an oxygen inlet valve which is controlled by a diaphragm which is in turncontrolled by the oxygenpressure on one side thereof and adjustable's'pring loading on the other side-thereof, the spring loading determining the.

pressure at which the valve'will Open.

A further object of the invention is toprovide a regulator embodying a valve which, although substantially independent of variationsin pres-i Further objects and advantages of the inven-' tion will be brought out in the following part ofthe specification.

Referring to the drawings which are for illus trative purposes only:

Fig. 1 is a View of an oxygen mask with the" regulator of my invention connected thereto;

Fig. 2 is a plan view of the regulator with a portion of the cover removed to disclose the internal mechanism thereof;

Fig. 3 is a transverse sectional view of the regulator taken on the line 3-3 of Fig. 2,

Fig. 4 is a detail view of the linkage which transfers the spring pressur on the adjusting mechanism to the diaphragm; Y J of the valve Fig. 5 is a detail-sectional-"viewand the lever mechanism for operating the same, taken on the line 5 of Fig. 3; and

Fig. 6 is a detail sectional view taken on the line 6-45 of Fig. 3, illustrating the adjusting mechanism.

As an example of one form in which the invention may be embodied, I have shown in the drawings a regulator, indicated generally at IE), comprising a main casing section I l and a cover l2 secured together by screws [3. Clamped between th casing sections H and: 1.2 is a diaphragm M which cooperates with the casing sections II and I2 to define a pair Of chambers I5 and I6.

Within the chamber I5 is avalve unit, indicated 5 generally at H, which controls the flow of oxygen into the chamber l5. Oxygen under pressure from a suitable source (such as an oxygen bottle) is delivered to the valve unit ll through a-connection l8 extending through the peripheral wall l9v ofthe casing section H,.the outer endof the connection I8 having a nipple v2!) for the attachment thereto. of an oxygen hose 21, Fig. 1. Oxygen isadmitted to the" chamber by the valve I! and flowsthrough an outlet port Zia (Fig. 3). in anoutlet connection 22., to a flexible hose 23 ota conventional oxygen mask 24. The mask 24 has an outlet. valve 25 for exhalation and. an inlet check valve 25" for inhalation. Inhalation is efiected by the flow from the connection 8 to the valve I 1,, thence into the chamberv l5, then through the outlet port 2! through the hose 23andthe inlet check valve and to the mask 24.

The valve I1 comprises a valve casing 26 having an end wall 2! formed with an. integral exterior valve seat 28" and having atits other end a threaded insert 25' providing an internal valve seat-'30. The, end wall?! and insert 29 are each provided with a 'pluralityof valve'ports '3'! and 32're'spectively, which are collectively of adequate area, to permit the oxygen to flow into the chamber-=15 at an adequate rate to satisfy normal requirements. A valve ticoop'erates with the valve seat mlt'o close the port '31 and awalveifl cooperates with the valve seat '30 to clos'e the port 32. The valves 33 and 34 are connected.- by :a stem35 which extends through the valve 33 and is threaded at 36 into the valve By threading or-untlrreading the stem-35in the valve 34,- the relative posit-ions of the two valves maybe ade justed so as to attain the proper cooperativeseatingyozf bot-h valves simultaneously; A look nut .3! is employed to lock the adjustments thus obtained, and as-pring 37a reacts between ashoulder 31-b-of said lock nut 31 andthe e-ndwa'll 2F! of thevalve casing for yieldingly ultgiIi-g'the-valve members 3'3-and 34-to the closedposition.

The valve seat 30 is of larger. diameter than the: valve seat 2-8:, whereby the-:fcrce resulting from. the pressure off the -oxygen appliedto the valve chamber 38 within the casing-26, tending to clcse the valve .34, somewhat greater than the force resulting from the pressure inithe charmber 58 tending to open the yak/e33; This differential Elf-$01308 is, hcwever, .relati-vel-ysmall, so that.

apslisght change .inzpressu-re in the. chamber 1 5 may be operative to 'open'and close the valve l?! through the medium of the diaphragm;! 4.

Thelinkage connectingthevalve I II to the diaphragm I4 includes. astem-alattached to -thevalve 34, a pin 4flrrnounted transversely in the stem'39, a bellcrank lever 4|v pivoted at 42. in a bracket 43 secured tothehousing member It, the bell crank lever 41 having. a pair 0f; relatively short arms 44 in which the ends of the pin 46 are mounted and relatively long arms 45, the

ends of which are formed with clevis members 46. Linked to the clevis members 46 by pins 41 5 are the arms of a yoke 48 which engages the under one of a pair of reenforcing discs 49 secured to the central area of the diaphragm M.

The cover member I2 is formed with a threaded collar 5| onto which is threaded an adjusting knob 52 having a hub portion 53 which projects into the collar 5!. The hub portion 53 bears against a compression spring 54 which in turn bears against a transverse member 55 of a lever 56.. The lever 56 (Fig. 4) is pivoted at one end, by -a.pivot:5l, to apair of ears 58 on a bracket 59 which issecured to the inner side of the cover member l2. The other end of the lever 56 is pivoted to the intermediate region of a pair of lever armsti by means of a pin 60 and slots 60a, zo' said lever arms 6| being pivoted, at 62, to ears 63 on the bracket 59. The lever arms .Blat their opposite ends are joined bya transverse bearing member 64 which bears against the disc-4'9 of the diaphragm 14.

By rotating-the knob 52 clockwise, it will be advanced toward the diaphragm I4, compressing the spring 54 and increasing the force withwhichv the bearing member 64 engages the disc45. The position of. adjustment is determined by a pin.- 30 rality of scale marks 55' .onthe dial face of the knob 52, cooperating with. ascale-mark 43.6 on the cover [2. Such numerals may indicate pressure of a water column or any other desired designation of. pressure. tained in any one of its several adjustedpositions by a spring 5? .having-adetent EBadaptedtoengage in any one of a plurality of notchesfiii in. The notches 89 correspondin position to the dial marks-65. The

the. hub member 53 (Fig. 6)..

4.0 spring 6? is the form olf aninverted yokehaving an apertured-web portion through which the spring 54 extends. The cover .I-Z andbracket 59 also are apertured to accommodate the spring 5 4;

In the operation of the invention, the force 43 exerted by the oxygenpressur-e in the chamber l5 will balance the force exerted :by the air pres sure in the chamber I B whichcommunicates-free ly with atmosphere, by means of peripherally; spaced openings I2a in the casing section i2;

plus the force exerted by-the lever 6i which.

turn is connectedthrough the, lever with the spring 54. When the user is not inhaling, these forces will 'balance the diaphragm vI4 in a neutral position in which the valves 33 and 34 will. 55 engage the seats 28 and 30 so as to seal ofl the escape of oxygen from the connection l8 into The valves will be heldin-closed the chamber l5. position by the linkage, including the stem -39,

the lever 4i and the yoke 48, since the latteris attached to the disc 43' which inturn is attached to the diaphragm. The amount of. closingiorce exerted through the linkage is slight, however, and the seating of the valves is assisted by the slight d'iiierential of the force resulting from the 5 oxygen pressure in the valve chamber 38, against the valve 34 tending to close the valve, over. the- The knob is yieldingly repressure from the connection l8'into the chamber l5. This flow will continue as long as the user inhales so as to continue the evacuation of the chamber [5, but as soon as inhalation ceases, the flow 'of' oxygen will rapidlyrestorethe pressure in the chamber to the previous level at which the diaphragm I4 is moved backto neutral posi-v tion, closing the valve 11. Exhalation will then cause the exhalation valve in the mask 24 to open to discharge the exhaled'gases. The'exhalation valve 25..is setto. open at a predetermined differential between the pressures in the mask 24 and the tube 23 which is caused by the build up of pressure in the mask 24 caused by exhalation.

The bell crank lever 4| gives a mechanical advantage such as to cause the valve H to open and close in response to slight variations in pressure in the chamber IS.

The lever mechanism, which transmits the spring force to the top of the diaphragm, provides an inverse mechanical advantage between spring and diaphragm. This allows the use of a relatively high rate spring, yet provides the equivalent of a low-rate spring in its application of force to the top of the diaphragm, this compression being provided by one rotation or less of the adjusting knob.

I claim as my invention:

1. An oxygen demand regulator for an oxygen mask having a breathing connection comprising: a pressure sensitive diaphragm; means cooperating with said diaphragm to define a pressure chamber; outlet means for said chamber adapted to be connected only to the breathing connection of said oxygen mask so that inhalation through said connection may lower the pressure in said chamber; a valve within said chamber comprising a valve casing having opposed outlet ports and a pair of valve seats associated with said ports and disposed respectively interiorly and ex= teriorly of said casing; a pair of valve elements cooperating with the respective valve seats; an inlet connection to said valve casing for delivering into said casing oxygen under pressure which will result in fluid forces acting against said valve elements in opening and closing directions respectively with a slight difierential in the closing direction, whereby said valves may respond to slight opening and closing forces to respectively permit the flow of oxygen under pressure into said chamber and to seal ofi said connection from the escape of oxygen into said chamber; and linkage connecting said diaphragm to said valve and adapted to operate same in response to inhalation and exhalation.

2. An oxygen demand regulator comprising: a diaphragm; a pair of casing members secured together with said diaphragm clamped therebetween to define a pressure chamber and a balancing chamber; an outlet for said balancing chamber connected to atmosphere; a single outlet for said pressure chamber; a valve in said pressure chamber, including a valve casing having a plurality of outlet ports and valve members cooperating with said ports, a valve stem movable substantially parallel to said diaphragm and at tached to said valve members for transmitting opening and closing movements thereto; an inlet to said valve casing for admitting oxygen under pressure; linkage connecting said valve stem to said diaphragm for transmitting diaphragm movement to the valve members, said linkage comprising a bell'cranklever: having ashor-t armpi'voted to said valve stem and a pair of long arms embracing said valve casing, and a yoke having a pair ofarms. embracing said valve casing and pivoted to said bell crank arms, said yoke including a central portion secured tosaid diaphragm; and means,- including a force modifying leverage system, in said balancing chamber for exertinga variable force against said diaphragm to bal- ?ance the force resulting from the pressure of oxygen in said chamber acting against the other side of said diaphragm.

3. An oxygen-demand regulator for an oxygen mask having a breathing connection, comprising: a pressure sensitive element; means cooperating with said element to define a pressure chamber; an outlet for said chamber adapted to be connected to the breathing connection of said oxygen mask so that inhalation through said connection may lower the pressure in said chamber; a valve in said chamber for controlling the flow of oxygen therethrough, said valve comprising a casing having opposed outlet ports and a pair of valve seats associated with said ports, one interiorly and the other exteriorly of said casing, the interior valve seat being of very slightly larger diameter than the exterior valve seat, and a pair of valve elements connected together for simultaneous movement and cooperating with said valve seats; an inlet for delivering into said valve casing oxygen under pressure which will result in fluid forces acting against said. valve elements tending to open one and to close the other with a small difl'erential of force in the closing direction which assists in maintaining said valve closed; and linkage connecting said valve elements to said pressure sensitive element for opening and closing said valve elements in response to respective movements of said pressure sensitive element and efiecting opening of said valve in response to inhalation through said breathing connection, said linkage being such as to multiply the forces applied by said pressure sensitive element to said valve elements.

4. An oxygen demand regulator comprising: a diaphragm; a pair of casing members secured together with said diaphragm clamped therebetween to define a pressure chamber and a balancing chamber; an outlet for said balancingchamber connected to atmosphere, said pressure chamber having an outlet; a valve in said pressure chamber, including a valve casing having a plurality of outlet ports and valve members coopcrating with said ports, a valve stem movable substantially parallel to said diaphragm and attached to said members for transmitting opening and closing movements thereto; an inlet to said valve casing, connected with a source of oxygen under pressure; linkage connecting said valve stem to said diaphragm for transmitting diaphragm movement to said valve elements, said linkage comprising a bell crank lever having a short arm pivoted to said valve stem and a pair of long arms embracing said valve casing, and a yoke having a pair of arms embracing said valve casing and pivoted to said bell crank arms, said yoke including a central portion secured to said diaphragm; a pair of levers in said balancing chamber operably pivoted to said casing and to each other, one of said levers having an arcuate part adjacent the free end thereof bearing against said diaphragm in opposition to the force resulting from oxygen pressure in said pressure chamber; a compression spring engaging the other of said levers; and an adjusting nut threadably connee-ted tho thBICH-Smg member which :defines said balancing chamber, and engaging. :said- :cnmpnessionspring.

REFERENCES GITED;

The idllowin'g" references are of record in the file-0f fihis pavtent':

"UNITED 'STA'IES -PATENTS Number Name Date 410,178 McElnoy ;Sept. 3,1889

Morris et a1. Mar. 23,1886

Number 8 Name Date Kenton,- June 9, i908 Jahn 41111112122, 190E! Chase Mar. 15,1910

Drager Mar. 9-, i915 Bryant Nov. .15., 192.7 'Goldkamp Jan. '3, 1933 Hughes Aug. 15', 1933' 'Hidbrink Feb. .2, 1913 Deming Feb. 2; 1943' Deming. Ju-nez19; 1945" Deming Oct. 16,1945 

